Improvement in telegraphic instruments



A. G. HOLCOMB, Telegrnph-Relay lnstrument.

Patented May ',1860.

Ila 1/61 560 UNITED STATES PATENT OFFICE.

ALFRED c. ammonia, or NEW YORK, N. Y.

Specification forming part of Letters Patent NO. 28,274, dated May 15, 1860.

To all whom it may concern:

Be it known that I, ALFRED G. HOLCOMB, of the city, county, and State of NcwYork, have invented a certain new and useful Improvement in Electric Telegraph Apparatus; and 1' do hereby declare the following to be a full, clear, and exactdescription thereof, reference being had to the accompanying drawings, making part of this specification.

The object of my said invention is to increase the movement of the armature-lever by allaying the residual magnetism in the relaymagnet after breaking the circuit of the main battery, as hereinafter explained; and theinvention further consistsin an arrangementt'or increasing the retentive capacity of the elecfro-magnet.

In the accompanying drawings, Figure l is a perspective view of the relay-magnet. 2 is a perspective view of my improved manipulator. Fig. 3 is a plan of the manipulator with thekey removed. Fig. Ms an under-side view of the key.

A is the base of the manipulator, provided at its four corners with binding-posts B B B B and near the center with metallic brackets (J C.

D represents a key the central portion of which is of non-conducting material, separatinglol-igitudinally the metallic sides (I d.

c c aremetallie pivotstapped into the brackets G C. The said pivots form the fulcrum of the key D and afford electrical connection with its respective sides.

E F G H are metalliepoints projecting upward from the base A, and each communicating with one end of the respective portions-d and d of the key as either end is depressed.

I is a spring serving to elevate the frontend of the key after depression, and so retain it while at rest.

J is the wooden base of the relay-magnet, provided at its four corners with bindingposts K K K K'.

The magnet L L may be of customary construction, but in the present illustration is provided with hollow of bush-cores l, of soft iron, interposed between the spools and the steel cores 1, by which means a greater amount of residual magnetism is retained.

M is the armatare-lerer, pivoted at the base in customary manner, and provided near the Fig.

top with a platina point, at. The armature N may be of either steel or soft irom O is the metallicstandard communicating with the vibrating end of the armature lever by the platinapoint 0. p is its insulating point or stop. The pointso and 1) are fixed in the ends of thumb-screws provided with customary cheek-nuts, as seen in thccra wings.

S is the spring employetkto d1 aw the armature-lever fronrthe magnet when released. The said spring is connectedby means of a silken cord, 8, with a thumb-screw, T, to permit the adjustment of its tension. The tension of the said spring is so adjusted as to equal in force the residual magnetism in the cores or armature, and thus hold the armature-lever midway between the points 0 and p, when the relay-magnet is disconnected from the main battery.

K and K are the binding-posts of the positive and negative wires of the local battery. and commmunicate with the standard 0 and armature-lever M, respectively, by com] ucting wires passing beneath the base.

The main conducting-wires are arranged and connected with the various parts of the apparatus as shown in the drawings, and as will be more fully understood from the following explanation of the operation of the apparatus.

While the apparatus is in its normal position the current passes from the platina or positive pole of the main battery over the wire 1 to the binding postB; thence over the wire 2 beneath the base to the bracket (3 and pivot c; thence over the side at of the key to the point'E; thence-over the wire 3 beneath the base to the binding-post B, and thence over the line-wire et to the bindingpost K of the magnet. It is then conducted by a wire beneath the base to the coil L, traverses this and the coil L, and passes overawire beneath the base to the binding-post K and earth-wire 7.

S is the earth-wire of the main battery, con nected to the binding-post B of the manipulater, from whence the current passes ben ath the base over the wire 9 to the'point F; thence over the side d of the key to the pivot c and bracket 6; thence over the wire 10 to the binding-post B and thence over the wirell to the zinc or negative pole of the main battery.

The effect of the above'described current is to magnetize the cores of the relay-magnet and draw the armature-lever toward the insulating-point 1), thus breaking the local circuit. Let the rear end of the key D be now elevated from the points E and I the circuit of the main battery will be broken, and the magnetism in the cores beinginsufificient to hold the armature-lever in contact with the insulatingpoint, it will be drawn by the spring S to its point of equilibrium between the points 0 and p; but a further depression of the front end of the key, bringing it in. contact with the points G and H, causes the current to flow from the platina pole over-the wire 1, post B, wire 2, bracket 0, side (I of key, stud G, wire 12, point F, wire 9, post B wires 8 and 7, post K, coils L and L, post K, wire 4, post B, wire 3, point B, wire 13, point H, side d of key, bracket 0, wire 10, postB and wire 11, to the zinc pole of the main battery, thus reversing the direction of the current through the coils of the relay-magnet and allaying its residual magnetism by partially changing its'polarity, the effect of. which is to enable the spring S to draw the platina point we in close contact with, the platina point 0, and thus complete the local circuit.

It will be seen that by the above-described arrangement of key, poinls,--and'iwires a single motion of the keyjs made to not only break or complete the circuit, as the case may be, but to first break it and .then complete it in rererse direction, thejefiect of which is to greatly increase the variations of the magnet in its active and inactive conditions and correspondingly increase the power exerted upon the armature-lever by the magnet and spring,

respectively.

It is well known that with the apparatus now in common use the presence of either electricity or moisture in the atmosphere renders it impossible to effect a sufllcient movement of the armature to produce intelligible signals. By the use of the reverse current I am enabled,

with a battery of a given power, to work efrent in the coils of the magnet, substantially.

as set forth.

2. The arrangement of the steel cores Z and iron bush-cores Z, in combination with the coils of the electro-magnet.

In testimony of which invention I hereunto set my hand.

ALFRED e. HOLGOMB.

Witnesses:

JOHN S. HOLLINGSH-EAD, JAMES H. Grammar. 

